The present invention relates to an artificial blood vessel for use in a region of a living body, which region needs to be repeatedly pierced with a needle.
Medical operations for replacing or bypassing a blood vessel in a living body with an artificial blood vessel, or artificial blood vessel grafting, are practiced in the medical field.
Some artificial blood vessels implanted in such operations are used in hemodialysis (dialysis treatment), for example, a blood passageway known as an arterial-venous (A-V) shunt interconnecting an artery and a vein, which is intended to be repeatedly pierced with a needle. One such artificial blood vessel (artificial prosthesis) is disclosed in British Patent No. 1506432, for example. The disclosed artificial blood vessel has a vessel wall comprising a single layer of expanded polytetrafluoroethylene (ePTFE).
The artificial blood vessel of such a structure has the disadvantage that, as it is repeatedly pierced with a needle, a number of holes are opened in the vessel wall, allowing the blood to leak therefrom.